| from typing import List | |
| class TreeNode: | |
| def __init__(self, x): | |
| self.val = x | |
| self.left = None | |
| self.right = None | |
| class Solution: | |
| def findFrequentTreeSum(self, root: TreeNode) -> List[int]: | |
| counter = dict() | |
| self.findFrequentTreeSumHelper(root, counter) | |
| result = [] | |
| maxCount = 0 | |
| for key, val in counter.items(): | |
| if val == maxCount: | |
| result.append(key) | |
| elif val > maxCount: | |
| result.clear() | |
| maxCount = val | |
| result.append(key) | |
| return result | |
| def findFrequentTreeSumHelper(self, root, counter): | |
| if not root: | |
| return 0 | |
| nodeSum = root.val | |
| leftSum = self.findFrequentTreeSumHelper(root.left, counter) | |
| rightSum = self.findFrequentTreeSumHelper(root.right, counter) | |
| nodeSum += leftSum + rightSum | |
| if nodeSum not in counter: | |
| counter[nodeSum] = 0 | |
| counter[nodeSum] += 1 | |
| return nodeSum | |
| root = TreeNode(5) | |
| root.left = TreeNode(2) | |
| root.right = TreeNode(-3) | |
| ob = Solution() | |
| print(ob.findFrequentTreeSum(root)) |